@moozooh Actually neither one is, they're both onomatopeias for loud mumbling when thinking, with the first one being used in japanese and the second one in english, just like "wan" is the same as "woof" but with different connotations.
On this particular case, I believe the translator used "fumu" because it looked cute.
@VladDracul2 Ackshually, common onomatopoeias are words, and they are recognized as such by dictionaries and thesauri. For example, "hmm" is listed as an interjection or an exclamation in Merriam-Webster, Longman, Macmillan, and Oxford. "Fumu" isn't, of course.
What's the difference in connotation between "wan" and "woof", though?
@ShockSword
Agreed. She and Yoshi would be even more so if Gamo did something stylish with that mop on her head, and Yoshi lost the childlike twintails(though they are cute).
In other news, Sistoro's unlit eyes remind me of a shark.